1. Technical Field
The present principles relate generally to Quick Response (QR) Codes and, in particular, to optimizing Quick Response Code capacity using Gray luminance.
2. Description of the Related Art
QR Code®, which is the abbreviated form of “Quick Response Code”, is the trademark for a type of two-dimensional barcode (or matrix barcode). A barcode is essentially an optically machine-readable label that is attached to item and can include information, e.g., for that item.
Quick Response Codes were first designed for the automotive industry. However, Quick Response Codes have recently become popular outside that industry due to their fast readability and large storage capacity compared to standard Universal Product Codes (UPCs). A Quick Response Code includes Black modules (square dots) arranged in a square pattern on a white background. The encoded information can be made up of four standardized types (“modes”) of data (numeric, alphanumeric, byte/binary, and Kanji), or through supported extensions, virtually any kind of data.
In the prior art, White blocks in a Quick Response Code have been used for hidden messages. However, there is a need for further capacity for Quick Response Codes.